ORIGINAL RESEARCH
Optimizing Tree Species Classification by Leveraging Median Filtering and Hybrid Feature Sets from Worldview Satellite Imagery
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1
School of Geography and Tourism, Luoyang Normal University, Luoyang, Henan Province, 471934, China
 
2
School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui Province, 230009, China
 
 
Submission date: 2026-01-11
 
 
Final revision date: 2026-04-14
 
 
Acceptance date: 2026-04-23
 
 
Online publication date: 2026-09-21
 
 
Corresponding author
Huaipeng Liu   

Luoyang Normal University, City of Luoyang , Henan Province, China, 471934, luoyang, China
 
 
 
KEYWORDS
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ABSTRACT
The high-precision tree species identification results based on remote sensing are of importance in forest inventory, management, and biodiversity protection. To evaluate whether the median filtering technique can effectively improve tree species identification accuracy, this study utilized WorldView-2 and WorldView-3 imagery as data sources and applied different sizes of filter kernels to them. Subsequently, tree species classification was performed using the random forest (RF) and Extreme Gradient Boosting (XGBoost) algorithms to explore the extent to which the identification accuracy could be improved under different filter kernel sizes and whether combining the optimal filtering results with the original spectral bands could further enhance the accuracy. The results showed that the filter kernel size of median filtering had a significant impact on tree species identification accuracy, and that within a certain range, larger filter kernels could yield higher accuracy. In WorldView-3, the accuracy of tree species identification reached 68.95±0.68% (RF), whereas in WorldView-2, the accuracy reached 82.04±0.30% (RF) after processing with an appropriate filter kernel. When the optimal filtering features were combined with the original spectral bands, the accuracy was further improved to 68.28±0.94% in WorldView-3 (RF) and to 85±0.09% in WorldView-2 (XGBoost), representing an improvement of approximately 7% in WorldView-3 and 8% in WorldView-2 compared with the unfiltered imagery (61.64±0.35% in WorldView-3 and 77.13±0.15% in WorldView-2). The experimental results demonstrate that median filtering can effectively improve tree species classification accuracy.
CONFLICT OF INTEREST
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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